@EricFielding @bascule I think I'm thick-headedly missing your point:
All power systems (& indeed most systems) are like this. My local utility has to have enough capacity, of whatever kind, for when everyone in town has their electric heater on in cold weather and also has their Xmas light blazing on the roof. My car engine has to have enough capacity to start off up a steep grade with four occupants & a trunkful of luggage, but it usually operates on level ground carrying just me and a 12 oz water bottle. City storm drains have to be able to accommodate a bomb cyclone, but they just sit there dry half the time even in the PNW.
Is it a problem that solar energy generation shares this feature?